Industrial Control Panels

New article 409 has been added to the 2005 edition of the National Electrical Code (NEC). Based on a proposal that there are many misapplications of control products and that the need for rules governing the installation of control panels is long overdue, this new article is long on product standards and short on any installation requirements not already covered by the NEC that will enhance safety related to the installation of industrial control panels.

Are we cluttering up the Code?

This article failed in the proposal stage because less than two-thirds of the members voted affirmatively on it. The negative comments appeared to be generally directed toward the proposal containing “product safety standards” that are already covered in existing product safety standards. Certainly with any control panel listed by an approved organization, misapplication should not be a problem. Misapplication in construction would run afoul of UL 508(A) and misapplication in adhering to installation requirements would run contrary to existing Code requirements. At the present time, UL 508A contains the required product standards for listed industrial control panels with all of the marking requirements including “short circuit rating” and is available to all inspection authorities.

The major concerns of the majority of the panel members about this proposal appear to be the idea that the authority having jurisdiction has no guidance in the approval of the construction of unlisted industrial control panels and their installation.

Listing is not a requirement for all electrical equipment addressed by the NEC, but following the manufacturers instructions included in any listed or labeled product is clearly shown in 110.3(B). Will addressing the problem of unlisted industrial control panels by inserting a part of the product standard in an installation safety code properly fix the problem? A more viable solution may be requiring field evaluation by a representative from a nationally recognized testing laboratory, which is a manner available to inspection authorities.

Comments were submitted pointing out that while the installation requirements included in the proposal were a duplication of requirements found elsewhere in the Code, this duplication of installation requirements supports the efforts of the Technical Correlating Committee to improve the usability of the Code by locating all of these requirements in each area. This of course, is far from being the object of the usability task groups. It appears to suggest that all references to other Code articles would be abolished and the referenced material would be duplicated in every area where the reference is made. This type of thinking will get us into Code volumes in a short time.

Other comments suggested that rather than a new article, the material should be included in existing Article 430 instead. This way it may have had a more logical basis for inclusion in the Code, but the panel steadfastly maintained that the establishment of a separate article of requirements for industrial control panels would make them easier to find and apply.

List all industrial control panels?

Apparently the problem of construction and installation of unlisted industrial control panels, in the opinion of the panel, is a safety consideration of such magnitude that the NEC must address it. An alternative would be to require listing of all industrial control panels to be assured that the product safety standard construction requirements are followed and recognize that all of the installation requirements are already a part of the NEC without attempting to centralize them in this article.

Appropriately, this new article was subjected to the proposal stage and the comment stage of the Code process before being accepted as a new article in the 2005 NEC. But at least one panel member entered a negative vote during the comment stage, expressing his contention that too many significant changes were made to the original proposal without opportunity for public review.

Significantly, the suggestion that the requirements now a part of Article 409 be put into Article 430 as a revised Part VIII would have caused the many references made to sections of Article 430 to be unnecessary as they are already in place in that article. This suggested change of course was not subject to public review but was not rejected for that reason because the panel agreed that locating the industrial control panel requirements in a separate article would make them easier to find and apply.

The article as now written will probably not cover adequately all of the product safety requirements and the authority having jurisdiction will still be required to make determinations that should be made by an organization that is concerned with evaluation of products.

Only time will tell and be the judge of the importance of the acceptance of this new article “Industrial Control Panels,” and determine whether it will make approval and acceptance by the authority having jurisdiction an easier job.

TROUT answers the Code Question of the Day on the NECA Web site. He can be reached at 352.527.7035.